Hand rock-drilling machine



Y (No Model.)

R, MAGILIL.

V jAND ROGKVDRILLING MACHINE.

N0. 292,665. Patente'dJaJ'n. 29,1884;

UNrrE. STATEsQ TENT .rricisg HAND ROCK-DRILLING MACHINE.

SPECIFICATION formingpart of Letters Patent No. 292,665, dated January29, 1881.

' Application filed m 20, 1883. (Yo model.)

1"0 all whom it may concern.-

Be it known that 1, ROBERT MAGILL, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented certain new anduseful Improvements in Hand Rockblow of the drill is obtained bydistcnding or compressing a spring attached to or bearing on thedrill-rod, and then releasing the spring and drill-rod from engagement.

The invention consists in the combinations and arrangements of parts,substantially as hereinafter fully described and claimed.

A designates a frame orhousin g, having the parallel slides a a andbottom b, the latter perforated to receive and guide the-drill-rod B,whose upper end is guided by means of cross-Head o, fitting the slides aa, as shown. A powerful coiled spring, (I, has its upper end fastened tothe cross head c or drill-rod B, and its lower end is anchored to theframe A, in any suitable manner. By this construction, if the rod 13 isforced upwardly, it distends the spring cl, and upon release of spring(I pulls the rod downwardly with great force, and causes the drill-bit6, set in the lower end of rod D, to strike violently into the rock orother material under operation. The cross-head 0 has toes f projectingto the front and rear, respectively.

Fitting to move freely in suitable guides, g, on the two sides of frameA, are the two similar bars H, having their inner faces provided withtoothed racks, as shown, which mesh at opposite ends, of a diameter withthe pinion I, whose shaft k is journaled in frame A, as shown, andisprovided with removable handlever l for operation. By oscillating thelever Z the pinion I causes the two rack-bars H to move in oppositedirections and to reciprocate,so that when one rack-bar is at itshighbar H, but allows the bar a to be pushed out of said recess readily.At each end of bars a a trigger-arm, 'r, rigidly attached to or a partthereof, extends inwardly, so as to project across the path of thecross-head toes f. Thus each of the bars a has two triggerarms, 1',embracing the frame A.

Upon each side of frame A, at a point at or near the highest travel ofthe bars n, are constructed the inclines s, projecting in the path ofbars at, so that when the latter move upwardly they mount the inclinesand the trigger-arms '1' are drawn out of the path of. the toes f. The

apparatus is placed together with one rackbar at the highest point,(which is as shown in drawings,) and the other at the lowest. latter isthen in such position that its trigger arms r extend under the toes f ofcross-head 0. By now oscillating the lever l the cross-head is lifted bythe rising rack-bar, and the other rack-bar descends, its trigger-arms1' swinging aside to pass the ascending cross-head toes f. The latterrises with the rack-bar, and the bar n of the latter finally mounts theincline s, and its trigger-arms '1' are drawn out from under the toes f,whereupon the spring d acts and violentlyimpels the drill-roddownwardly. Upon now moving the lever Z in the opposite direction thesame operations are repeated by the other rack-bar, and so. on, thuseffecting a powerful blow of the-drill at every oscillation of thehand-lever.

To permit the rotation of the drill, the rod B is so fitted tocross-head c as to revolve therein. Such can be done by the well-knownarrangement of collar or pins. Rod B may be tubular or solid, ascircumstances may die tate. If hollow, the drill-bit may be long, and

then can be clamped at different lengths, to

adapt it to deep or shallow drilling. By replacing the bit a by ahammer-head the apparatus may be used in connection with the ordinaryhand-drill, in that case the apparatus taking the place of the usuallaborious striking with a sledge.

To eii'ect the progressive rotation of the drill-rod and bit while inoperation, I place a pinion, 1, on the drill-rod B, below frame A, andon the sides of said frame I set the wheels '1, meshing with pinion 1.One of the wheels 0 is fitted with a locking-pawl, x, to prevent returnmovement. The bars H are elongated or provided with extensions eachcarrying a spring-dog, arranged to strike one of the teeth of wheels 1*every time the bar II is de pressed and push it a slight distance-sayone tooth, :ly this means the drill-rod and bit are partially rotatedafter every blow.

I have shown the bars H as outside the frame A; but they may be arrangedinside and the pinion I reduced accordingly in diameter. Such reductionwould limit the throw of the bars H too much, and to avoid suchconsequences I would adopt the common mechanical expedient of multiplegearing-1 0., apply the lever l to the shaft of a large pinion whichwould engage (out of the line of bars H) with the pinion I.

I claim as my invention 1. In a drilling apparatus, the combination ofthe oscillatory pinion I, leverl on the shaft thereof, rack-bars H,engaging with said pinion, and spring-actuated drill-rod B, said bars Hbeing provided'with means for engaging the rod B and automaticallyreleasing the same, substantially as described.

2. The combination of oscillatory pinion I, reciprocating rack-bars H,engaging therewith, frame A, having guides g for said rackbars,spring-triggers p n 1', drill-rod B, spring (I, and cross-head 0, havingtoes f, said triggers adapted to engage the cross-head in their upwardmovement and yield in the downward movement, substantially as described;

3. The reciprocating bar H,-having recess m, in combination with thecross-bar 11 having notch 0, lugs j), and arms 1', and spring q, and'thedrill-rod B, having cross-head c, and toes f in the path of said arms1', substantially as described.

4. The combination, with drill-rod B, having toes f, of reciprocatingbars H, having spring trigger-arms r, and frame A, provided withinclines s, substantially as described.

In testimony that I claim the foregoing as my own I have hereto afiixedmy signature in presence of two witnesses.

ROBERT MAGILL.

\Vitnesses:

'lnoams J. lar'rnnsox, T. J. Mc'lronn.

